import java.io.IOException;
import java.net.*;
import java.util.Scanner;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User:
 * Date: 2025-06-19
 * Time: 20:37
 */
public class UdpEchoClient {
    private DatagramSocket socket = null;

    private String serverIP;
    private int serverPort;

    public UdpEchoClient(String serverIP, int serverPort) throws SocketException {
        this.serverIP = serverIP;
        this.serverPort = serverPort;
        socket = new DatagramSocket();
    }

    public void start() throws IOException {
        Scanner scanner = new Scanner(System.in);

        while(true) {
            //1.从控制台读取用户的输入内容
            System.out.println("请输入内容");
            if (!scanner.hasNext()) {
                break;
            }
            String request = scanner.next();

            //2.把请求发送给服务器，需要构造DatagramPacket对象
            DatagramPacket requestPacket = new DatagramPacket(request.getBytes(), request.getBytes().length, InetAddress.getByName(serverIP), serverPort);

            //3.发送数据包
            socket.send(requestPacket);

            //4.接收服务器的响应
            DatagramPacket responsePacket = new DatagramPacket(new byte[4096], 4096);
            socket.receive(responsePacket);

            //5.从服务器读取的数据打印出来
            String response = new String(responsePacket.getData(), 0, responsePacket.getLength());
            System.out.println(response);
        }
    }

    public static void main(String[] args) throws IOException {
        UdpEchoClient client = new UdpEchoClient("127.0.0.1",9090);
        client.start();
    }
}
